Answer:
If you try to lift up a weight in a swimming pool and then try to lift the same weight on the edge of the pool, it feels much lighter in the water.
This was supposed to have been first explained by the Greek scientist Archimedes. He said that the water gives an upward force or upthrust on any object in it.
You can weigh an object in air and then in water and actually work out the upthrust, it is the difference between the two readings. For this reason the upthrust is often called the loss in weight of the object.
That could be an electromagnet,
and it could also be an solenoid.
Scientists need a standard system of measurement to allow for consistency with measurement data (A). Scientists would not be able to understand what other scientists are saying if everyone uses their own system of measurement. Scientists need to take measurements, interpret them and communicate the results to other scientists. That is why a standardized system of taking measurements has been developed. The International System of Units or the Metric system is the measurement system of choice for scientists all over the world today.
Answer:
Obviously the answer is Sun...
By Newton's second law, the net force on the object is
∑ <em>F</em> = <em>T</em> - <em>mg</em> = - <em>ma</em>
where
• <em>T</em> = 25 N, the tension in the string
• <em>m</em> is the mass of the object
• <em>g</em> = 9.8 m/s², the acceleration due to gravity
• <em>a</em> = 2.0 m/s², the acceleration of the elevator-object system
Solve for <em>m</em> :
25 N - <em>m</em> (9.8 m/s²) = - <em>m</em> (2.0 m/s²)
==> <em>m</em> = (25 N) / (9.8 m/s² - 2.0 m/s²) ≈ 3.2 kg